Violin bow frog



Feb. 12, 1957 A. F. GARDNER VIOLIN BOW FROG Filed Nov. 17, 1953 r E a::m

' INVENTOR ALBERT E GARDNER ATTORNEYS Uited States This inventionrelates to violin bow construction, and more particularly has referenceto the frog conventionally applied to one end of the bow in a manner toslide longitudinally of the bow back, for placing under tension the hairof the bow.

it is conventional practice to mount a frog for sliding movementdirectly upon the back of the bow, the frog being adjustablelongitudinally of the bow back by means of a screw that extends into theback or shank of the bow and has threaded engagement with a followersecured to the frog.

This conventional construction has certain notable deficiencies. Afterthe bow has been used for some time, warpage of the bow tends to developin the area in which is located the conventional longitudinal slotthrough which the follower extends from the screw into the frog. As aresult, the continuous strain imposed upon the bow back by reason of thetensioning of the hair of the bow will in many instances split the endof the bow above the screw.

A second deficiency which has been noted arises from the tendency of theside edges of the slot to become worn, as a result of which the frogtwists out of alignment with the bow when the bow is in use.

In view of the above, it has been the main object of the presentinvention to provide a violin bow frog construction which will eliminatethe tendency of the bow toward warpage, thus to prevent splitting, andwhich will further keep the frog tight upon the bow at all times. Byproviding a frog construction that will meet these desirable objects, 1propose to give longer life to the bow while at the same time assuringits proper functioning whenever it is in use.

It is further proposed to provide a violin bow frog which will beparticularly designed for use with nylon strands of hair, though it isalso capable of use with the conventional horse hair strands.

A still further object is to provide a violin bow frog construction asdescribed, wherein the hair can be easily mounted within the frog, thusto permit the bow to be re-haired swiftly and easily.

A still further important object of the present invention is to providea violin bow frog construction as stated which will meet the severaldesirable objects set forth above, but which will at the same time becapable of manufacture at relatively low cost.

Other objects will appear from the following description, the claimsappended thereto, and from the annexed drawing, in which like referencecharacters designate like parts throughout the several views, andwherein:

Figure l is a perspective view of a violin bow equipped with a frogformed in accordance with the present invention;

Figure 2 is a longitudinal sectional view, on an enlarged scale, of saidfrog;

Figure 3 is a transverse sectional view taken on line 3-3 of Figure 2;and

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Figure 4 is a sectional view, the scale being enlarged still further,taken on line 44 of Figure 2.

Referring to the drawings in detail, 10 designates a back or shank of aviolin bow, this being of generally conventional construction. As may benoted from Figure 2, the frog-supporting end of the back is of hexagonalcross sectional configuration, but it is believed worthy of note thatother cross sectional shapes can be used if desired.

At one end, the back 10 is provided with the conventional tip 12, towhich is connected one end of the hair 14. I prefer to use nylon hair,since I have found that not only does this provide a clearer tone whilebeing much stronger than the conventionally employed horse hair, butalso it is readily formed to uniform lengths, a characteristic which isparticularly valuable in view of the specific frog construction which Ihave designed.

The invention includes an elongated tube 16 of a suitable metalmaterial, said tube being formed to a cross sectional configurationcomplementing that of the bow back. The tube 16 is open at one end, toreceive the bow back in a manner particularly Well shown in Figure 2,the tube sliding longitudinally of the back but being held againstrotation relative to the back by reason of the non-circular crosssectional shapes of the tube and back.

The other end of the tube projects beyond the tubesupporting end of thebow back, and is of closed formation, said closed end of the tube beingprovided with a smooth walled opening 18. A fiber washer 20, having asmooth walled opening registering with the opening 18, is positionedwithin the tube, and is placed against the closed end of the tube, inthe preferred embodiment of the invention, as a wearing washer betweenthe end wall of the tube and a flange 21 secured to the shank 26 of anadjusting screw, to provide an abutment bearing against thewasher-protected end Wall of the tube.

I provide a nut 22, which is loose within the tube, but which is heldagainst rotation by reason of the complementary non-circular crosssectional shape of the nut and tube. The nut rests against the adjacentend of the back ll), and is provided with a threaded opening 24registering with the openings of the end wall of the tube and washer 2s.

Threadedly engaged in the opening 24 is the shank 26 of an adjustingscrew. One end of the screw extends into a smooth walled Socket 2'?formed in the adjacent end of the bow back 1d, the other end of thescrew projecting beyond the tube and being longitudinally ribbed asatZS.

A hand knob 3b is formed with a socket the wall of which iscomplementary to the longitudinal ribs of the screw, whereby the knobmay be applied to the projecting portion of the screw, to provide aconvenient means for rotating the screw when it is desired to adjust thefrog longitudinally of the bow back. The knob 30 abuts against the endwall of the tube 16, and thus, when the knob is rotated, it will effectmovement of the tube 16 longitudinally of the bow back.

Rigid with an intermediate portion of the tube 16, and projectinglaterally from the tube, is a prong 32, that is disposed obliquely tothe axis of the tube. The prong is removably positioned within anangular bore 34 formed in a frog body 36, thus to connect the frog bodydetachably to the tube and cause movement of the frog body jointly withthe tube when the tube is adjusted longitudinally of the back It The topsurface of the frog body, that is, that surface thereof that engages thetube 16, is longitudinally recessed complementarily to the surface ofthe tube (see Figure 3), thus to interfit the frog body and tube andgreases W prevent lateral deviation of the frog body relative to thetube.

Formed upon the inner end of the frog body 36 is a reduced tongue 40 ofD-shaped cross sectional configuration. In the flat underside of thetongue 4% there is formed a shallow recess 42 the side walls of whichconverge toward the frog end of the bow (see Figure 4). The hair 12 isextended through said recess 42, for positioning of the hair within anindentation 44 formed in the bottom surface of the frog body, saidindentation 44 having an angularly disposed inner or bottom wall, as maybe readily noted from Figure 2. The indentation 44 is in communicationwith one end of an opening 46, said opening being formed at its otherend with a counterbore 48 opening upon the outer end surface of the frogbody.

A knot 50 is formed on the end of the hair 12 and is seated in thecounterbore 48, to hold the strands of the hair 12 in said frog, thus toconnect the hair to the frog body.

'Formed in the bottom surface of the frog body 36, and communicatingwith the indentation 44, is a shallow longitudinal recess 52, saidrecess being in communication with a dovetailed recess 54 formed. in theouter end surface of the frog body. A bottom plate 56 is shaped to fitsnugly within the bottom longitudinal recess 52 of the frog body, and isformed at one end with a wedging lip 58 underlying the hair 12. AD-shaped ferrule 60 is then positioned removably over the wedging lipand tongue 44 so as to extend thereabout, said ferrule being soproportioned as to force the wedging tongue and lip toward one another,thus to clamp the hair 12 securely therebetween.

An end plate 62 is provided, said end plate being slidable into and outof the recess 54 of the end surface of the frog, and covering the knot50 under normal conditions. The end plate 62 has an angularly extendedlower end portion (see Figure 2), that laps the contiguous end of thebottom plate 56.

It will be readily appreciated that in re-hairing the bow, it isnecessary merely that the knot 5d be formed at the ends of the strandsof hair, after the hair is extended through the opening 46 andcounterbore 4%, the knot then being seated within the counterbore 48.The hair is tightened and the bottom plate 56 is applied, so as to coverthe indentation 44 and cause the wedging lip 58 to be positioned underthe hair 12. The ferrule 60 is then positioned as illustrated in thedrawings, and the end plate 62, which will have been previously appliedto the frog body, will then be held securely in place.

In adjusting the frog body longitudinally of the back of the bow, theuser rotates the hand knob 3%, as a re sult of which the tube 16 isadjusted longitudinally of the back of the bow. The axial movement ofthe tube body is effective to shift the frog body longitudinally of thebow, thus to place the hair 12 under a selected tension.

It is believed worthy of note that the construction illustrated anddescribed is one which prevents warpage of the bow back, since said backneed only be bored to a slight extent to receive the shank 26, and canbe left nearly solid at the frog end thereof. Further, the constructionis one which prevents lateral deviation of the frog body relative to thebow during use of the bow, this being prevented by reason of theinterfitting of the body and tube illustrated in Figure 3, and beingprevented further by reason of the complementary cross sectional shapeof the tube 16 and back 10. Of course, when it is desired to remove thebody 36 for any reason, as for example, when it is desired to re-hairthe bow, it is merely necessary to rotate the knob 30 to an extentsufficient to place slack in the hair 12, after which the body 36 can bereadily slipped off the prong 32.

It is believed apparent that the invention is not necessarily confinedto the specific use or uses thereof debody carried by scribed above,since it may be utilized for any purpose to which it may be suited. Noris the invention to be necessarily limited to the specific constructionillustrated and described, since such construction is only intended tobe illustrative of the principles of operation and the means presentlydevised to carry out said principles, it

eing considered that the invention comprehends any minor changes inconstruction that may be permitted within the scope of the appendedclaims.

What is claimed is:

1. In a violin bow frog the combination, with the hair and back of aviolin bow, of a tube slidably mounted upon the back; a frog bodycarried by the tube; means connecting the hair to the body; a nut seatedagainst one end of the back; a screw threadedly engaged with the nut;and abutment means on the screw bearing against the tube, said screwbeing effective to shift the body longitudinally of the back responsiveto the threading of the screw within the nut, thereby to tension thehair selectively.

2. In a violin bow frog the combination, with the hair and back of aviolin bow, said back being of non-circular cross section at one end, ofa tube of complementary cross section slidably mounted upon the back; afrog the tube; means connecting the hair to the body; a nut seatedagainst said end of the back; a screw threadedly engaged with the nut;and abutment means on the screw bearing against the tube, said screwbeing effective to shift the body longitudinally of the back responsiveto threading of the screw within the nut, thereby to place the hairunder a selective tension.

3. In a violin bow frog the combination, with the hair and back of aviolin bow, said back being of non-circular cross section at one end, ofa tube of complementary cross section slidably mounted upon the back; afrog body detachably connected to the tube; means connecting the hair tothe body; a nut seated against said end of the back, the back having asocket formed in said end thereof; a screw threadedly engaged with thenut and extending into said socket; and abutment means on the screwbearing against the tube, said screw being effective to shift the bodylongitudinally of the back responsive to threading of the screw withinthe nut, thereby to place the hair under a selective tension.

4. In a violin bow frog the combination, with the hair and back of aviolin bow, said back being of non-circular cross section at one end, ofa tube of complementary cross section slidably mounted upon the back; aprong projecting laterally from the tube; a frog body having a borereceiving said prong for detachable connection of the body to the tube;means connecting the hair to the body; a nut seated against said end ofthe back; a screw threadedly engaged with the nut, the back having asocket formed in said end thereof receiving the screw; and abutmentmeans 011 the screw bearing against the tube, said screw being effectiveto shift the body longitudinally of the back responsive to threading ofthe screw within the nut, thereby to place the hair under a selectedtension.

5. In a. violin bow frog the combination, with the hair and back of aviolin bow, said back being of non-circular cross section at one end, ofa tube of complementary cross section slidably mounted upon and havingone end projecting beyond said end of the back; a prong projectinglaterally from the tube; a frog body having a bore receiving said prongfor detachable connection of the body to the tube; means connecting thehair to the body; a nut seated against said end of the back and heldagainst rotation by the tube; a screw extending into the projectingportion of the tube and threadedly engaged with the nut, said end of theback having a socket receiving said screw; and abutment means on thescrew bearing against the tube, said screw being effective to shift thetube and the body longitudinally of the back responsive to threading ofthe screw Within the nut, thereby to place the hair under a selectedtension.

greases 6. 'In a violin bow frog the combination, with the hair and backof a violin bow, said back being of non-circular cross section at oneend, of a tube of complementary cross section slidably mounted upon andhaving one end projecting beyond said end of the back; a prongprojecting laterally from the tube and arranged obliquely to the axis ofthe tube; a frog body having a bore arranged to receive said prong fordetachable connection of the body to the tube; means connecting the hairto the body; a nut seated against said end of the back and held againstrotation by the tube; a screw coaxial with the tube and extending intothe projecting portion thereof, said end of the back having a socket andthe screw extending into the socket; and abutment means on the screwbearing against said one end of the tube, said screw being threadedlyengaged with the nut to impart axial movement to the tube and bodylongitudinally of the back responsive to threading of the screw withinthe nut, thereby to place the hair under a selected tension.

7. In a violin bow frog the combination, with the hair and back of aviolin bow, said back being of noncircular cross section at one end, ofa tube of complementary cross section open at one end to receive saidend of the back, said tube being slidably mounted upon the back andhaving its other end projecting therebeyond; a prong projectinglaterally from the tube and arranged obliquely to the axis of the tube;a frog body having a bore arranged to receive said prong for detachableconnection of the body to the tube; means connecting the hair to thebody; a nut seated against and held against rotation by said end of theback; a screw coaxial with the tube and threadedly engaged in said nut,said end of the back having a socket and the screw extending within thetube and having one end disposed in said socket, said screw having ahand knob on its other end abutting against the projecting end of thetube; and abutment means on the screw bearing against said projectingend of the tube, said screw being threadedly engaged with the nut toimpart axial movement to the tube and body longitudinally of the backresponsive to rotation of the knob to thread the screw within the nut,thereby to place the hair under a selected tension.

8. In a violin bow frog the combination, with the hair and back of aviolin bow, of a frog body slidably mounted upon said back, said bodyhaving communicating recesses formed in its outer end surface and in itsbottom surface respectively, the body being additionally formed with anangular indentation communicating with the recess of the bottom surfaceand with an opening communicating at opposite ends with said indentationand with the recess of the outer end surface, said indentation andopening being adapted to receive the hair of the how; a knot formed onthe hair at one end and seated in said opening, said knot beingaccessible through the recess of the outer end surface; a reducedwedging tongue formed upon the inner end of the body; a bottom plateremovably seated in the recess of the bottom surface of the body tocover said indentation and formed at one end with a wedging lipunderlying said tongue, the hair extending between the tongue and saidwedging lip; a ferrule adapted to extend about the tongue and wedginglip, said ferrule being proportioned to force the tongue and wedging liptoward one another to wedge the hair therebetween; and an end platepositioned in the recess of the outer end surface and having one endangularly extended, to extend into the recess of the bottom surface ofthe body, said end of the end plate and the other end of the bottomplate lapping one another within the recess of the bottom surface.

References Cited in the file of this patent UNITED STATES PATENTS1,784,038 Augustine Dec. 9, 1930 2,479,505 Nathan Aug. 16, 19492,483,486 Brown Oct. 4, 1949 2,592,715 Lesinsky Apr. 15, 1952 2,624,225Nebel Jan. 6, 1953

